Effect of propofol on transforming growth factor-β1/Smad2 signaling pathway in lung tissues in rats with lipopolysaccharide-induced acute lung injury / 中华麻醉学杂志

ABSTRACT

Objective To investigate the effect of propofol on transforming growth factor (TGF)-β1/Smad2 signaling pathway in lung tissues in rats with lipopolysaccharide (LPS)-induced acute lung injury (ALI).Methods Fifty-six male Wistar rats,aged 7-8 weeks,weighing 260-300 g,were randomly divided into 5 groupscontrol group (group A,n =8) ; LPS group (group B,n =12); 3 propofol groups (groups C,D,E,n =12).ALI was induced by intravenous LPS 8 mg/kg in groups B,C,D and E.In groups C,D,E,propofol 5 mg/kg was injectedintravenously before LPS administration and at 0 and 1 h after LPS administration,respectively,followed by infusion of propofol at 10 mg· kg-1 · h-1 until 5 h after LPS administration.Group A received the equal volume of normal saline.Arterial blood samples were collected immediately before LPS administration and 1,3 and 5 h after LPS administration for determination of pH value and PaO2.Then the animals were sacrificed and the lungs were immediately removed for calculation of the wet/dry lung weight ratio and for determination of the expression of TGF-β1-mRNA and Smad2 in lung tissues.Results Compared with group A,pH value and PaO2 were significantly decreased,wet/dry lung weight ratio was increased and the expression of TGF-β1 mRNA and Smad2 was up-regulated in groups B and E (P ＜ 0.05).Compared with group B,pH value and PaO2 were significantly increased,wet/dry lung weight ratio was decreased and the expression of TGF-β1 mRNA and Smad2 was down-regulated in groups Cand D,and PaO2 was significantly increased in group E (P ＜ 0.05).Conclusion The mechanism by which propofol alleviates ALI induced by LPS is related to inhibition of TGF-β1/Smad2 signaling pathway.